Non-wicking container

ABSTRACT

A method for fabricating a container which comprises coating the edges of a roll of paper with an aqueous composition comprising a vinyl polymer with reactive groups and a halo-metallic Werner type complex, cutting the paper into individual units and sealing each paper unit to form a container. Also, the resulting container.

United States Patent Thomas 1 Dec. 2, 1975 NON-WICKING CONTAINER 3,092,248 6/1963 Lilflfi! ct ill 229/22 X 3,145,905 8/1964 Moore 229/48 T [75] Inventor: Manuel Thomas Spartanburg- 3,149,019 9/1965 Skotnicki CK 2114.. 161/93 x 3.166.226 1/1965 Mobley 229 7 R 73 Assigneez Deering Millikan Research 3 2/1968 Wheeler 229/7 R Corporation, Spartanburg, SC. 7 Primary Examiner-Davis T. Moorhcad Filed May 1974 Attorney, Agent, or Firm-H. William Pctry; Arthur L. [21] Appl. No.: 472,411 Urban 1521 US. Cl. 229/48 T; 229/22; 117/126 GO ABSTRACT llllt. CLZ 1 1 A method for fabricating a Container Comprises [581 Fleld of Search 229/22, 48 T, 48 SC; coating the edges of a roll of p p with an aqueous l 17/126 composition comprising a vinyl polymer with reactive groups and a halo-metallic Werner typc complex, cut- References C'ted ting the paper into individual units and sealing each UNITED STATES PATENTS paper unit to form a container. Also, the resulting 2,544,668 3/1951 Goebcl ct a1 117/126 GQ Container- 2,662,835 12/1953 Reid 3.032251 5/1962 Jarund 229/48 T 5 Clams 3 Drawmg Flgures U.S. Patent Dec. 2, 1975 3,923,238

other fibrous material. Such wicking or absorption of the contents discolors and/or weakens the paper and may cause the container to leak.

A wide variety of proposals have been suggested for eliminating or minimizing this problem. For example, it is well known to fabricate a container from paper with surface coatings. Such coatings may eliminate seepage through the paper but usually do not eliminate the wicking at the edges of the paper which are exposed to the contents. It also has been proposed to employ a container with an inner seamless lining. While this may solve the wicking problem, it is not an ideal solution due to the increased cost and the additional steps required in fabricating such a container.

It has been proposed that certain coatings be applied to the edges of paper, for example, US. Pat. Nos. 3,187,480 and 3,364,050. However, these coatings have not been satisfactory due to a lack of resistance to certain liquids, difficulties in application, excessive cost and the like.

The present invention provides a novel method for fabricating a container which minimizes the wicking or absorption of the contents. Moreover, the container of the invention is conveniently fabricated on conventional machinery.

The novel method of the invention comprises coating the edges of a roll of paper with an aqueous composition comprising a vinyl polymer with reactive groups and a halo-metallic Werner type complex, cutting the paper into individual units, and sealing the edges to each other to form a container. Generally, the aqueous composition contains between about 0.5 and percent solids by weight and preferably about 1 to 2 percent.

The aqueous composition employed to coat the edges of a roll of paper in accordance with the invention as pointed out above comprises a vinyl polymer with reactive groups and a halo-metallic Werner type complex. The reactive groups of the vinyl polymer may be hydroxyl, carboxyl, amide, sulfonyl and similar groups. Suitable vinyl polymers include homopolymers and copolymers of vinyl acetal, vinyl acetate, vinyl alcohol, vinyl pyrrolidone, acrylic acid, polyethylene ionomers and the like. Advantageously, the vinyl polymer is polyvinyl alcohol and preferably is a fully hydrolized polyvinyl alcohol.

The halo-metallic Werner type complex employed in combination with the vinyl compound advantageously is a fatty acid compound. Preferably, the complex is a chrome complex and most preferably a chrome complex of a fatty acid. Suitable fatty acids include about ten to twenty carbon atoms.

The vinyl polymer and the Werner type complex react in accordance with the invention to form a film on the edges of the paper which is resistant to oil, grease, water and solvents.

The invention will be described in greater detail with reference to the accompanying drawings in which:

FIG. 1 is one form of container of the invention;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1; and

FIG. 3 is a schematic illustration of one form of apparatus for coating paper in accordance with the method of the invention.

. As shown in FIG. 1, a tetrahedron container 11 is formed from a sheet of paper 12 which is folded along .lines 13 and sealed at seams 15, 16 and 17. Seams l5 and 16 are outside seams and seam I7 is an overlapping seam in which coated edge 18 of the paper is exposed to the contents of the container.

In FIG. 3, a roll of paper 20 is coated on its edges 21 by spraying a composition stored in container 23. The composition in container 23 is pumped by pump 24 through line 25 and filter 26 to a spray nozzle 27 from which it is expelled onto the edges 21 of paper roll 20.

The invention will be further illustrated by the following examples in which parts and percentages are by weight unless otherwise specified.

EXAMPLE I Sixty parts of a fully hydrolized polyvinyl alcohol (PVA) sold by DuPont as Elvanol 71-30 dispersed in 440 parts cold water with agitation and then heated to C and maintained at that temperature for 15 minutes to dissolve the polymer. Thereafter, 420 parts of cold water are added to the solution and the diluted solution cooled to ambient temperature. Eighty parts of a chrome complex of stearic acid sold by DuPont as Quilon C are added to the solution.

The resulting mixture containing 8% Quilon C (wet) and 6% PVA solids is applied to the edges of a roll of 30 lb./ 108 lb. laminated paper until the edges are completely covered. The paper roll is then dried in an oven at 250300F.

The treated paper and an untreated control paper are tested for wicking by dipping strips thereof into a 0.5 percent by volume chloramine blue solution including 1 percent of an ethoxylated nonyl phenol surfactant for a period of 15 seconds. The paper treated in accordance with the invention shows no blue discoloration while the untreated control paper shows a discoloration which extends /2 inch from the edge.

Packages fabricated from the treated paper show no discoloration or weakening of the structure even after ten days storage when filled with milk, cream, ice cream, grape juice and similar materials.

EXAMPLE [I The procedure of this Example is the same as that of EXAMPLE I except that the composition applied to the edges of the rolls of paper comprises a vinyl acetate polymer sold by Union Carbide as Ucar Latex l5, Quilon C and sufficient water to provide 6% solids Ucar Latex, and 8% Quilon C.

Wicking tests conducted with the treated paper and untreated control paper reveal the same superiority for the treated paper of the invention as the comparison set forth in EXAMPLE I.

EXAMPLE III The procedure of this Example is the same as that of EXAMPLE I except the composition applied to the edges of the rolls of paper comprises 16 parts of an amide reactive vinyl polymer sold by Monsanto as Monflex 4514, 6 parts (wet) of Quilon C and 78 parts of water.

Wicking tests conducted with the treated paper and untreated control paper reveal the same superiority for the treated paper of the invention as the comparison set forth in EXAMPLE I.

The above description and drawings show that the present invention provides a novel method for fabricating a container which minimizes wicking or absorption of the contents therein which may result in discoloration and/or leaking of the container. Furthermore, the novel container of the invention is conveniently fabricated with conventional production techniques and machinery.

it will be apparent that various modifications in the detailed procedures disclosed above and shown in the drawings may be made within the scope of the invention. For example, different techniques for applying the coating composition to the edges of the paper rolls may be employed, e.g., brush or wiper application, roller coating, etc. Therefore, the invention is to be limited only by the following claims.

That which is claimed is:

1. A container comprising a paper unit with edges sealed to each other and edges located on the inside of the container coated with the reaction product of a vinyl polymer with reactive groups and a halo-metallic Werner type complex.

2. A container according to claim 1 wherein the vinyl polymer is a polyvinyl alcohol.

3. A container according to claim 1 wherein the vinyl polymer is a fully hydrolized polyvinyl alcohol.

4. A container according to claim 1 wherein the halo metallic Werner type complex is a chrome complex.

5. A container according to claim 1 wherein the halometallic Werner type complex is a chrome complex of afatty acid. 

1. A CONTAINER COMPRISING A PAPER UNIT WITH EDGES SEALED TO EACH OTHER AND EDGES LOCATED ON THE INSIDE OF THE CONTAINER COATED WITH THE REACTION PRODUCT OF A VINYL POLYMER WITH REACTIVE GROUPS AND A HALO-METALLIC WERNER TYPE COMPLEX.
 2. A container according to claim 1 wherein the vinyl polymer is a polyvinyl alcohol.
 3. A container according to claim 1 wherein the vinyl polymer is a fully hydrolized polyvinyl alcohol.
 4. A container according to claim 1 wherein the halo-metallic Werner type complex is a chrome complex.
 5. A container according to claim 1 wherein the halo-metallic Werner type complex is a chrome complex of a fatty acid. 